Several of the epigenetic enzymes targeted by these drugs, such as DNA methyltransferases (DNMTs), histone deacetylases (HDACs), the histone demethylase (HDM) LSD1/KDM1A and the histone methyltransferases (HMTs) EZH2 and G9A, play a role in the transcriptional repression of TEs in cancer cells (Figure 5). The gene discussed is EHMT2; the disease is cancer.